Camera module and electronic device

ABSTRACT

The present invention relates to a camera module in which a thin camera module can be realized at a low cost and an electronic device. The camera module includes a lens unit that stores a lens that condenses light on a light receiving surface of an image sensor; a rigid substrate on which the image sensor is disposed; and a flexible substrate electrically connected with the rigid substrate, wherein in the case where the light receiving surface of the image sensor locates at the top, the lens unit, the flexible substrate, and the rigid substrate are disposed in this order from the top.

CROSS-REFERENCE PARAGRAPH

The present application is a continuation application of U.S. patentapplication Ser. No. 14/408,110, filed Dec. 15, 2014, which is aNational Stage of PCT/JP2013/066912, filed Jun. 20, 2013, and claims thebenefit of priority from prior Japanese Patent Applications JP2013-111767, filed May 28, 2013, JP 2013-055149, filed Mar. 18, 2013,and JP 2012-147878, filed Jun. 29, 2012, each of the above-referencedapplications is hereby incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present technology relates to a camera module and an electronicdevice, and in particular, to a camera module in which a thin cameramodule can be realized at a low cost and an electronic device.

BACKGROUND ART

In a conventional camera module structure, FPC (Flexible PrintedCircuits) are disposed on the lower side of a module and are connectedby soldering or by ACF (Anisotropic Conductive Film) (for example, seePatent Document 1).

As such, the thickness of the FPC and the thickness of the connectingportion (solder connection or ACF connection) are included in the heightof the module such as a lens unit, whereby there is a problem that thethickness of the module increases.

Meanwhile, a rigid flexible substrate, in which a rigid portion and aflexible portion are integrated, may also be used. In that case, thereis no need to take into account a connection between the rigid substrateand the FPC.

CITATION LIST Patent Document

Patent Document 1: Japanese Patent Application Laid-Open No. 2009-033481

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

However, in the case of using a rigid flexible substrate, constraints onthe design increases, compared with the case of a configuration in whicha rigid substrate and FPC are connected, for example.

For example, in the case of using a rigid flexible substrate, as it isnecessary to conform the pitch of vias and the width of wiring to designrules of the flexible portion in the substrate, it is difficult toperform fine wiring in the rigid portion in the substrate.

Further, in the case of using a rigid flexible substrate, as a layerconstituting the flexible portion is inserted between layersconstituting the rigid portion, a range of process conditions such as anultrasonic wave, temperature setting, and the like becomes narrow whenan image sensor is wire-bonded, and the like.

Further, in the case of using a rigid flexible substrate, as a memberusage rate decreases in each of the layer constituting the rigid portionand the layer constituting the flexible portion, the substrate costincreases. As such, it is difficult to suppress the cost of the entirecamera module.

Further, in the case of using a rigid flexible substrate, whenattempting to change the shape of the flexible portion corresponding toa device (mobile telephone, smartphone, or the like) in which the cameramodule is incorporated, for example, it is necessary to redesign theentire substrate including the rigid portion. As such, the deliveryperiod of the substrate becomes longer, for example, and the costfurther increases.

The present technology is disclosed in view of such a situation, andaims to realize a thin camera module at a low cost.

Solutions to Problems

A first aspect of the present technology is a camera module including: alens unit that stores a lens that condenses light on a light receivingsurface of an image sensor; a rigid substrate on which the image sensoris disposed; and a flexible substrate electrically connected with therigid substrate, wherein in a case where the light receiving surface ofthe image sensor locates at the top, the lens unit, the flexiblesubstrate, and the rigid substrate are disposed in this order from thetop.

In the rigid substrate of a square shape, in an overlap region of a bandshape having a predetermined distance from an end of one side of thesquare, the rigid substrate is disposed to overlap a portion of theflexible substrate, and the rigid substrate and the flexible substrateare attached to each other.

The overlap region is a band-shaped region having a width of 2.4 mm orless.

In the flexible substrate, besides the overlap region, a reinforcedregion in which the flexible substrate overlaps the rigid substrate isprovided.

The reinforced region is provided to extend in parallel with two sidesof the image sensor of the square shape.

The reinforced region is provided to extend in parallel with one side ofthe image sensor of the square shape.

In the rigid substrate of a square shape, a solder resist is removed ina band-shaped region having a predetermined distance from an end of oneside of the square.

A groove for accommodating an end portion of the flexible substrate isformed in the lens unit.

A frame is further provided between the lens unit and the flexiblesubstrate.

A groove for accommodating an end portion of the flexible substrate isformed in the frame.

An electrode pad of the image sensor and an embedded electrode providedin the flexible substrate are connected with each other by wire bonding,and a signal output from the electrode pad of the image sensor istransmitted to the rigid substrate through the embedded electrode.

The embedded electrode is formed by punching all layers of the flexiblesubstrate having a multilayer structure to thereby form an opening, andembedding metal in the opening.

The electrode pad is formed by punching an uppermost layer of theflexible substrate having a multilayer structure to thereby form anopening, and embedding metal in the opening, and an electrode pad of theimage sensor and the electrode pad provided in the flexible substrateare connected with each other by wire bonding.

An electrode pad of the image sensor and a stud bump protruding on therigid substrate are connected by wire bonding.

An opening is formed by punching all layers of the flexible substratehaving a multilayer structure, and

the stud bump is formed on an electrode pad which is on the rigidsubstrate and is located at a position corresponding to the opening.

In the flexible substrate having a multilayer structure, an openingformed by punching all layers and an opening formed by punching anuppermost layer of the flexible substrate are provided in a regionconnected with an electrode pad of the image sensor by wire bonding.

In the first aspect of the present technology, in a case where the lightreceiving surface of the image sensor locates at the top, the cameramodule is configured such that the lens unit, the flexible substrate,and the rigid substrate are disposed in this order from the top.

A second aspect of the present technology is a camera modulemanufactured by a method including the steps of: disposing a rigidsubstrate; connecting a flexible substrate with the rigid substrate; anddisposing a lens unit on the rigid substrate, the lens unit storing alens that condenses light on a light receiving surface of the imagesensor, wherein in the step of connecting the flexible substrate withthe rigid substrate, in the rigid substrate of a square shape, in anoverlap region of a band shape having a predetermined distance from anend of one side of the square, the rigid substrate is disposed tooverlap a portion of the flexible substrate, and the rigid substrate andthe flexible substrate are attached to each other.

In the second aspect of the present technology, a rigid substrate isdisposed; a flexible substrate is connected with the rigid substrate;and a lens unit is disposed on the rigid substrate, the lens unitstoring a lens that condenses light on a light receiving surface of animage sensor, wherein in the step of connecting the flexible substratewith the rigid substrate, in the rigid substrate of a square shape, inan overlap region of a band shape having a predetermined distance froman end of one side of the square, the rigid substrate is disposed tooverlap a portion of the flexible substrate, and the rigid substrate andthe flexible substrate are attached to each other.

A third aspect of the present technology is an electronic deviceincluding a camera module including: a lens unit that stores a lens thatcondenses light on a light receiving surface of an image sensor; a rigidsubstrate on which the image sensor is disposed; and a flexiblesubstrate electrically connected with the rigid substrate, wherein in acase where the light receiving surface of the image sensor locates atthe top, the lens unit, the flexible substrate, and the rigid substrateare disposed in this order from the top.

In the third aspect of the present technology, in a case where the lightreceiving surface of the image sensor locates at the top, the cameramodule is configured such that the lens unit, the flexible substrate,and the rigid substrate are disposed in this order from the top.

Effects of the Invention

According to the present technology, a thin camera module can berealized at a low cost.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating an exemplary configuration ofa conventional camera module.

FIG. 2 is a side view explaining an exemplary configuration of aconventional camera module.

FIG. 3 is a side view illustrating an exemplary configuration of amodification of the camera module illustrated in FIG. 2.

FIG. 4 is a side view explaining an exemplary configuration of a cameramodule to which the present technology is applied.

FIGS. 5A and 5B are another side views explaining an exemplaryconfiguration of a camera module to which the present technology isapplied.

FIG. 6 is a plan view of the camera module illustrated in FIGS. 5A and5B, seen from the upper direction of FIGS. 5A and 5B.

FIG. 7 is another plan view of the camera module illustrated in FIGS. 5Aand 5B, seen from the upper direction of FIGS. 5A and 5B.

FIG. 8 is a plan view illustrating a detailed exemplary configuration ofa frame of FIG. 7.

FIG. 9 is a cross-sectional view of the frame taken along an alternatelong and short dash line A-A′ of FIG. 8.

FIG. 10 is a plan view illustrating another detailed exemplaryconfiguration of the frame of FIG. 7.

FIG. 11 is a cross-sectional view of the frame taken along an alternatelong and short dash line A-A′ of FIG. 10.

FIG. 12 is a plan view of the camera module illustrated in FIGS. 5A and5B, seen from the upper direction of FIGS. 5A and 5B.

FIG. 13 is a plan view illustrating a configuration of a flexiblesubstrate and a rigid substrate, illustrated in FIG. 12, in detail.

FIGS. 14A, 14B, 14C, 14D, 14E and 14F are diagrams illustrating anexemplary manufacturing process of a camera module to which the presenttechnology is applied.

FIG. 15 is a diagram explaining another configuration of a flexiblesubstrate in a camera module to which the present technology is applied.

FIG. 16 is a diagram explaining still another configuration of aflexible substrate in a camera module to which the present technology isapplied.

FIG. 17 is a side view explaining a necessary distance which is adistance from an end of an image sensor to an end of a rigid substrate.

FIGS. 18A and 18B are plan views seen from above of FIG. 17.

FIG. 19 is a diagram illustrating an example in which an electrode padof an image sensor and a flexible substrate are directly connected witheach other.

FIGS. 20A and 20B are diagrams explaining punching of a flexiblesubstrate.

FIGS. 21A and 21B are side views explaining a method of connecting arigid substrate and a flexible substrate.

FIG. 22 is a plan view seen from above of FIGS. 21A and 21B.

FIGS. 23A and 23B are side views explaining another example of a methodof connecting a rigid substrate and a flexible substrate.

FIG. 24 is a side view explaining still another example of a method ofconnecting a rigid substrate and a flexible substrate.

FIG. 25 is a diagram illustrating an enlarged connecting portion betweenthe flexible substrate and the rigid substrate of FIG. 24.

FIGS. 26A and 26B are diagrams explaining punching of the uppermostlayer of a flexible substrate.

FIGS. 27A and 27B are diagrams explaining a configuration of the entireflexible substrate configured by including the uppermost layerillustrated in FIGS. 26A and 26B.

FIG. 28 is an enlarged view of part of electrode pads and a connectionterminal portion in FIG. 18A.

FIG. 29 is a diagram illustrating an example in which an electrode padof a rigid substrate and a terminal of a connection terminal unit aremade common.

FIG. 30 is an enlarged view of part of a terminal group of FIG. 29.

FIG. 31 is a cross-sectional view corresponding to FIG. 18B.

FIG. 32 is a cross-sectional view corresponding to FIG. 29.

FIG. 33 is a block diagram illustrating an exemplary inner configurationaccording to an embodiment of a mobile telephone to which the presenttechnology is applied.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the technology disclosed herein will bedescribed with reference to the drawings.

FIG. 1 is a perspective view illustrating an exemplary configuration ofa conventional camera module. A camera module 10 illustrated in thefigure is to be installed in an electronic device such as a mobiletelephone or a smartphone.

The camera module 10 in FIG. 1 is configured of a lens unit 11, a frame12, a rigid substrate 13, and a flexible substrate 14. A flexiblesubstrate is also referred to as FPC (Flexible Printed Circuits).

The lens unit 11 is a unit which stores a lens of the camera, and thelike. Light condensed through the lens in the lens unit 11 forms animage on a light receiving surface of an image sensor, described below,whereby an image is captured.

The frame 12 is a standardized connecting component to be used forconnection with the rigid substrate 13, for example, and is also usedfor improving shielding property, and the like. It should be noted thatthe frame 12 may not be provided. In that case, the lens unit 11 isdirectly attached to the rigid substrate 13.

The rigid substrate 13 is a substrate on which an image sensor of thecamera is disposed, for example.

The flexible substrate 14 is a substrate on which wiring for inputtingand outputting signals, input or output to/from the camera module 10,to/from another unit of an electronic device is printed, for example. Inthe example of FIG. 1, the flexible substrate 14 is attached to thebottom surface (surface on the lower side in the figure) of the rigidsubstrate 13.

FIG. 2 is a side view explaining an exemplary configuration of theconventional camera module 10. It should be noted that in the cameramodule 10 illustrated in FIG. 2, the frame 12 in FIG. 1 is not providedand the lens unit 11 is directly attached to the rigid substrate 13.

Further, in the example of FIG. 2, the flexible substrate 14 is attachedto the bottom surface of the rigid substrate 13, which is the same asthe case explained with reference to FIG. 1. It should be note that inthis example, solder balls 21 used for attaching the flexible substrate14 and the rigid substrate 13 are illustrated.

The thickness (height in the figure) of the camera module 10, configuredas illustrated in FIG. 2, is represented as H1, and the height H1includes the thickness of the flexible substrate 14 and the thickness ofthe solder ball 21. Further, the length, in a horizontal direction inthe figure, of the camera module 10 is represented as L1. It should benoted that in this example, the length in the horizontal direction ofthe camera module 10 does not include a portion where only the flexiblesubstrate 14 exists.

However, as mobile telephones and smartphones are getting thinnerincreasingly in recent years, it is natural that thinner camera modulesare also expected.

As such, it is considered to use a rigid flexible substrate in which arigid portion and a flexible portion are integrated, for example. Inthat case, it is not necessary to consider connection between the rigidsubstrate and the flexible substrate.

However, in the case of using a rigid flexible substrate, constraints onthe design increases, compared with the case of a configuration in whicha rigid substrate and a flexible substrate are connected (attached) witheach other.

For example, in the case of using a rigid flexible substrate, as it isnecessary to conform the pitch of vias and the width of wiring to thedesign rules of the flexible portion in the substrate, it is difficultto perform fine wiring in the rigid portion in the substrate.

Further, in the case of using a rigid flexible substrate, as a layerconstituting the flexible portion is inserted between layersconstituting the rigid portion, a range of process conditions such as anultrasonic wave, temperature setting, and the like becomes narrow whenan image sensor is wire-bonded.

Further, in the case of using a rigid flexible substrate, as a memberusage rate decreases in each of the layer constituting the rigid portionand the layer constituting the flexible portion, the substrate costincreases. As such, it is difficult to suppress the cost of the entirecamera module.

Further, in the case of using a rigid flexible substrate, whenattempting to change the shape of the flexible portion corresponding toa device (mobile telephone, smartphone, or the like) in which the cameramodule is incorporated, for example, it is necessary to redesign theentire substrate including the rigid portion. In that case, the deliveryperiod of the substrate becomes longer, for example, and the costfurther increases.

Meanwhile, as illustrated in FIG. 3, the rigid substrate 13 may beconfigured to protrude from the bottom surface of the lens unit 11 inorder to reduce the thickness of the entire module to thereby allow theflexible substrate 14 to be attached on the surface (surface on theupper side in the figure) of the rigid substrate 13.

In the case of configuring the camera module 10 as illustrated in FIG.3, as the thickness of the flexible substrate 14 and the thickness ofthe solder ball 21 are canceled, the thickness of the camera module 10is H2, which is less than H1. As such, it is possible to configure thecamera module 10 to be thinner, compared with the case of FIG. 1.

However, in the case of configuring the camera module 10 as illustratedin FIG. 3, as the rigid substrate 13 extends in a horizontal directionin the figure by a length a, the length of the entire camera module inthe horizontal direction in the figure also extends. In the example ofFIG. 3, the length of the camera module 10 in the horizontal directionin the figure is L2 which is larger than L1.

As such, in the case of configuring the camera module 10 as illustratedin FIG. 3, for example, a mobile telephone, a smartphone, or the likemust be designed while taking into account an increase in the length ofthe camera module 10 in the horizontal direction.

In view of the above, the present technology configures a camera moduleas illustrated in FIG. 4, for example.

FIG. 4 is a side view explaining an exemplary configuration of a cameramodule 50 to which the present technology is applied. It should be notedthat in the camera module 50 illustrated in FIG. 4, the frame describedin FIG. 1 is not provided, and a lens unit 51 is directly attached tothe rigid substrate 53.

Further, in the camera module 50 illustrated in FIG. 4, a left endportion, in the figure, of a flexible substrate 54 is interposed betweenthe lens unit 51 and the rigid substrate 53.

The camera module 50, to which the present technology is applied, isconfigured such that only an end portion on the left side, in thefigure, of the flexible substrate 54 is attached to an end portion onthe right side, in the figure, of the surface of the rigid substrate 53.Further, in the camera module 50 to which the present technology isapplied, a groove for accommodating the left end portion of the flexiblesubstrate 54 is provided on an end portion on the right side, in thefigure, of the lens unit 51, the details of which will be describedbelow.

In the case of configuring the camera module 50 as illustrated in FIG.4, as the thickness of the flexible substrate 54 and the thickness ofthe solder ball are canceled, the thickness of the camera module 50 isH2. As such, it is possible to configure the camera module to bethinner, compared with the case of FIG. 1.

Further, in the case of configuring the camera module 50 as illustratedin FIG. 4, the length of the camera module 50 in the horizontaldirection in the figure is L1. Accordingly, the length of the entirecamera module in the horizontal direction in the figure does not extend,as in the configuration illustrated in FIG. 3.

Further, in the case of configuring the camera module 50 as illustratedin FIG. 4, the length of the flexible substrate 54 in the horizontaldirection in the figure can be configured to be shorter. For example,the flexible substrate 54 in FIG. 4 is configured to have a lengthshorter by a length L3 in the horizontal direction in the figure,compared with the case of the flexible substrate 14 in FIG. 1, forexample.

Accordingly, in the case of configuring the camera module 50 asillustrated in FIG. 4, the area of the flexible substrate can be reducedby the amount corresponding to the length L3, compared with theconfiguration of FIG. 1. This means that by applying the presenttechnology, the area of an expensive flexible substrate is reduced,whereby the cost of the entire camera module can also be reduced.

FIGS. 5A and 5B are another side views explaining an exemplaryconfiguration of the camera module 50 to which the present technology isapplied. FIG. 5A is a diagram illustrating an exemplary configuration onthe case where a frame is not provided in the camera module 50, and FIG.5B is a diagram illustrating an exemplary configuration of the casewhere a frame is provided in the camera module 50.

In the camera module 50 illustrated in FIG. 5A, a left end portion, inthe figure, of the flexible substrate 54 is interposed between the lensunit 51 and the rigid substrate 53.

The camera module 50, to which the present technology is applied, isconfigured such that only an end portion on the left side, in thefigure, of the flexible substrate 54 is attached to an end portion onthe right side, in the figure, of the surface of the rigid substrate 53.Further, in the example of FIG. 5A, a groove 51 a for accommodating theleft end portion of the flexible substrate 54 is formed in an endportion on the right side, in the figure, of the lens unit 51.

In the camera module 50 illustrated in FIG. 5B, a frame 52 is providedbetween the lens unit 51 and the rigid substrate 53, and a left endportion, in the figure, of the flexible substrate 54 is interposedbetween the frame 52 and the rigid substrate 53. Further, in the exampleof FIG. 5B, a groove 52 a for accommodating the left end portion of theflexible substrate 54 is formed in an end portion on the right side, inthe figure, of the frame 52.

If the groove 51 a or the groove 52 a is not formed, for example, theright side in the figure of the lens unit 51 floats due to the thicknessof the flexible substrate 54, whereby there is a possibility that thelight condensed by the lens in the lens unit 51 does not form an imageappropriately on the imaging surface of the image sensor on the rigidsubstrate 53. Here, in order to allow the light condensed by the lens toform an image appropriately on the imaging surface of the image sensor,it is necessary that the parallel degree of the top surface (surface onthe upper side in the figure) of the lens unit 51 and the imagingsurface of the image sensor 61 becomes 1.5 degrees or smaller.

It should be noted that as the lens unit 51 or the frame 52 is attachedto the rigid substrate 53 with an adhesive or the like, by adjusting thethickness of the adhesive, for example, it is possible to perform tiltadjustment so as to set the focus position of the lens in the lens unit51 to be appropriate.

Further, if the groove 51 a or the groove 52 a is not formed, the rightside, in the figure, of the lens unit 51 floats due to the thickness ofthe flexible substrate 54. As such, the adhesive must be injected inextra amounts for that portion, into a left-side portion in the figure.As such, the attachment strength of the lens unit 51 or the frame 52 maybe insufficient, or light transmitted through the adhesive may leak inthe image sensor.

However, if an adhesive having high shielding property is injected in alarge amount in such a manner that the surface of the rigid substrate 53and the bottom surface of the lens unit 51 (or the frame 52) becomeparallel to each other in a state where the flexible substrate 54 isinterposed, the camera module may be configured without forming thegroove 51 a or the groove 52 a.

FIG. 6 is a plan view of the camera module 50 illustrated in FIGS. 5Aand 5B, viewed from the upper direction of FIGS. 5A and 5B. It should benoted that in FIG. 6, the lens unit 51 and the frame 52 are notillustrated for easy understanding.

As illustrated in FIG. 6, a rectangle image sensor 61 is disposed on thealmost center of the rigid substrate 53. It should be noted that in thefigure, the front side of the sheet is the imaging surface of the imagesensor 61. As illustrated in the figure, a portion on the left side, inthe figure, of the flexible substrate 54 overlaps a portion on the rightside, in the figure, of the rigid substrate 53. In the overlappedportion, the flexible substrate 54 and the rigid substrate 53 areattached, or electrically connected, to each other.

Further, as illustrated in FIG. 6, the flexible substrate 54 is disposedon the rigid substrate 53 (on the light receiving side of the imagesensor 61).

FIG. 7 is another plan view of the camera module 50 illustrated in FIGS.5A and 5B, viewed from the upper direction of FIGS. 5A and 5B. In thecase of FIG. 7, an illustration of the frame 52 is added, which isdifferent from FIG. 6.

As illustrated in FIG. 7, a portion on the left side, in the figure, ofthe flexible substrate 54 overlaps a portion on the right side, in thefigure, of the frame 52, and the flexible substrate 54 is disposed underthe frame 52. Further, the center of the frame 52 is formed as a cavity,whereby the imaging surface of the image sensor 61 is seen.

FIG. 8 is a plan view illustrating a detailed exemplary configuration ofthe frame 52 of FIG. 7. This figure is a diagram illustrating the frame52 seen from the lower direction (rear side of the sheet) of FIG. 7, inwhich the bottom surface of the frame 52 is illustrated. As illustratedin FIG. 8, the groove 52 a is formed on the right side, in the figure,of the frame 52. It should be noted that the center portion of the frame52 is formed as a cavity, as described above.

FIG. 9 is a cross-sectional view of the frame 52 taken along thealternate long and short dash line A-A′ of FIG. 8. As illustrated in thefigure, the groove 52 a is formed on the right side in the figure.

FIG. 10 is a plan view illustrating another detailed exemplaryconfiguration of the frame 52 of FIG. 7. This figure is a diagramillustrating the frame 52 seen from the lower direction of FIG. 7, inwhich the bottom surface of the frame 52 is illustrated. As illustratedin FIG. 10, the groove 52 a is formed on the right side, in the figure,of the frame 52. It should be noted that the center portion of the frame52 is formed as a cavity, as described above.

In the example of FIG. 10, the groove 52 a is formed across the rigidsubstrate 53 from the top to the bottom in the figure, which isdifferent from the case of FIG. 8. The groove 52 a may be formed in thisway.

FIG. 11 is a cross-sectional view of the frame 52, taken along thealternate long and short dash line A-A′ of FIG. 10. As illustrated inthe figure, the groove 52 a is formed on the right side in the figure.

It should be noted that while the case where the groove 52 a is formedin the frame 52 has been described herein, this also applies to the casewhere the groove 51 a is formed in the lens unit 51. This means that thegroove 51 a may be formed across the entire lens unit 51 from the top tothe bottom as in the case of FIG. 10, or the groove 51 a may be formedin such a manner that the upper side and the lower side of the lens unit51 are left, as in the case of FIG. 8.

Meanwhile, on the surface of the rigid substrate 53, a solder resist(SR) serving as an insulation film protecting the circuit pattern, forexample, is provided. However, as described with reference to FIGS. 5A,5B, 6, 7, 8, 9, 10 and 11, in the case of attaching the flexiblesubstrate 54 to the surface of the rigid substrate 53 so as to beelectrically connected with each other, the SR must be removedbeforehand in a portion of the surface of the rigid substrate 53, inorder to connect a connection terminal of the flexible substrate 54 anda connection terminal of the rigid substrate 53 with each other.

FIG. 12 is a plan view of the camera module 50 illustrated in FIGS. 5Aand 5B, viewed from the upper direction of FIGS. 5A and 5B. It should benoted that in FIG. 12, the lens unit 51 and the frame 52 are notillustrated for easy understanding.

As illustrated in FIG. 12, the rectangle image sensor 61 is disposed onthe almost center of the rigid substrate 53. As illustrated in thefigure, a portion on the left side, in the figure, of the flexiblesubstrate 54 overlaps a portion on the right side, in the figure, of therigid substrate 53. In a portion on the right side, in the figure, ofthe rigid substrate 53, the SR is removed and a connection terminalportion 53 a is formed.

Further, even in the flexible substrate 54, a connection terminalportion is formed in a portion on the left side in the figure. However,in FIG. 12, as a connection terminal portion is provided on the rearface of the flexible substrate 54, it is not illustrated.

The connection terminal portion 53 a of the rigid substrate 53 and theconnection terminal portion, not illustrated, of the flexible substrate54 are provided with connection terminals, respectively, and theconnection terminal of the rigid substrate 53 of the rigid substrate 53and the connection terminal of the flexible substrate 54 are attached,whereby the rigid substrate 53 and the flexible substrate 54 areconnected electrically.

FIG. 13 is a plan view illustrating the configuration of the flexiblesubstrate 54 and the rigid substrate 53 illustrated in FIG. 12, indetail. In the example of the figure, the image sensor 61 is illustratedin more detail. Further, a portion on the left side, in the figure, ofthe flexible substrate 54 overlaps a portion on the right side, in thefigure, of the rigid substrate 53. In FIG. 13, the overlapped portion isillustrated as an overlap width W.

The overlap width W is represented as a distance from an end potion ofone side (e.g., a side on the right side in FIG. 13) of a square rigidsubstrate, and in the band region of the overlap width W, the flexiblesubstrate 54 and the rigid substrate 53 are attached to each other in anoverlapped manner. In order to reduce the cost of the entire cameramodule by preventing the connection (attachment) with the flexiblesubstrate 54 from affecting the arrangement of the image sensor 61 andby reducing the area of the expensive flexible substrate, the overlapwidth W is desirably 2.4 mm or less, for example.

FIGS. 14A, 14B, 14C, 14D, 14E and 14F are diagrams explaining an exampleof a manufacturing process of a camera module to which the presenttechnology is applied.

First, as illustrated in FIG. 14A, the rigid substrate 53, on which acomponent 62 is mounted, is prepared. It should be noted that asdescribed with reference to FIG. 12, the SR is removed in a portion onthe right side, in the figure, of the rigid substrate 53, and theconnection terminal portion 53 a is formed.

Next, as illustrated in FIG. 14B, the flexible substrate 54 is attachedto the rigid substrate 53. In this step, the rigid substrate 53 and theflexible substrate 54 are attached to each other in the overlap width W,and the connection terminal disposed in the connection terminal portion53 a and the connection terminal of the flexible substrate 54 areattached to thereby be connected electrically.

It should be noted that for attaching the rigid substrate 53 and theflexible substrate 54, solder, an adhesive including solder, ACF, ACP,or the like is used.

Next, as illustrated in FIG. 14C, the image sensor 61 is die-bonded (DB)to the rigid substrate 53.

Then, as illustrated in FIG. 14D, wire-bonding (WB) is performed betweenthe image sensor 61 and the rigid substrate 53. In FIG. 14D, a wire 63is wire-bonded.

Next, as illustrated in FIG. 14E, an adhesive is applied. In FIG. 14E,an adhesive 64 is applied to both left and right sides of the rigidsubstrate 53. As the adhesive 64 used for adhesion between the rigidsubstrate 53 and the lens unit 51 (or adhesion between the rigidsubstrate 53 and the frame 52), resin which attenuates light is used.For example, black resin, resin containing filler, or the like is usedas the adhesive 64.

Finally, as illustrated in FIG. 14F, the frame 52 or the lens unit 51 isattached to rigid substrate 53. It should be note that in the drawing onthe left side of FIG. 14F, the frame 52 is attached to the rigidsubstrate 53, and in the drawing on the right side, the lens unit 51 isattached to the rigid substrate 53. Further, as described above, inorder to allow the light condensed by the lens to form an imageappropriately on the imaging surface of the image sensor, it isnecessary that the parallel degree of the top surface of the lens unit51 and the imaging surface of the image sensor 61 is 1.5 degrees orless.

The camera module to which the present technology is applied ismanufactured through this manufacturing process.

Meanwhile, in the present technology, the flexible substrate 54 and therigid substrate 53 are attached in the portion where a portion of theflexible substrate 54 overlaps a portion of the rigid substrate 53(overlap width). As such, according to the usage conditions of thecamera module, it may be desired to improve the break strength of theflexible substrate 54.

FIG. 15 is a diagram explaining another configuration of the flexiblesubstrate 54 in the camera module to which the present technology isapplied. This figure is a diagram corresponding to FIG. 6, and partscorresponding to those of FIG. 6 are denoted by the same referencesigns.

In the example of FIG. 15, a reinforced portion 54 a is provided to theflexible substrate 54. In this example, the reinforced portions 54 a,extending in a left direction in the figure, are provided to an end onthe upper side and an end on the lower side, in the figure, of theflexible substrate 54. This means that in the flexible substrate 54, thereinforced portions 54 a, extending in parallel with two sides of thesquare image sensor 61, are provided.

In addition to the overlap width described above, if the flexiblesubstrate 54 and the rigid substrate 53 are also attached to each otherin the reinforced portions 54 a, the area of the attached surfaceincreases, compared with the case of FIG. 6. Accordingly, in the case ofthe configuration of FIG. 15, it is possible to improve the breakstrength of the flexible substrate 54, compared with the case of FIG. 6.

Further, as the reinforced portions 54 a are provided at positions wherethey are not brought into contact with the image sensor 61, they do notaffect the arrangement of the image sensor 61.

By configuring the flexible substrate 54 as illustrated in FIG. 15, itis possible to improve the break strength of the flexible substrate 54according to the usage conditions of the camera module, for example.

Alternatively, the flexible substrate 54 in the camera module to whichthe present technology is applied may be configured as illustrated inFIG. 16. This figure is a diagram corresponding to FIG. 6, and the partscorresponding to those of FIG. 6 are denoted by the same referencesigns.

In the example of FIG. 16, a reinforced portion 54 b is provided to theflexible substrate 54. In this example, the reinforced portions 54 b,extending in an up and down direction in the figure, are provided to anend portion on the upper side and an end portion on the lower side, inthe figure, of the flexible substrate 54. This means that in theflexible substrate 54, the reinforced portions 54 b, extending inparallel with one side of the square image sensor 61, are provided.

In addition to the overlap width described above, if the flexiblesubstrate 54 and the rigid substrate 53 are attached to each other inthe reinforced portions 54 b, the area of the attached surfaceincreases, compared with the case of FIG. 6. Accordingly, in the case ofthe configuration of FIG. 16, it is possible to improve the breakstrength of the flexible substrate 54, compared with the case of FIG. 6.

Further, as the reinforced portions 54 b are provided at positions wherethey are not brought into contact with the image sensor 61, they do notaffect the arrangement of the image sensor 61.

By configuring the flexible substrate 54 as illustrated in FIG. 16, itis possible to improve the break strength of the flexible substrate 54according to the usage conditions of the camera module, for example.

Meanwhile, in the embodiment described above, description has been givenon the premise that the image sensor 61 and the rigid substrate 53 arewire-bonded, as described with reference to FIG. 14D.

The wire connected with the image sensor 61 bonded on the rigidsubstrate 53 is electrically connected with the connection terminaldisposed on the connection terminal portion 53 a through the wiringformed on the rigid substrate 53. Then, the connection terminal of therigid substrate 53 and the connection terminal of the flexible substrate54 are attached to each other, whereby the image sensor 61 and theflexible substrate 54 are connected electrically.

However, in the case of such a connection, there is a limitation in sizereduction of the camera module. This means that when attaching theflexible substrate 54 to the rigid substrate 53, an overlap width isrequired as described above, and further, a width for wire bonding isalso required between the image sensor 61 and the rigid substrate 53.Accordingly, the rigid substrate 53 is required to be larger by thewidth for at least the overlap width and the wire bonding, compared withthe image sensor 61.

FIG. 17 is a side view explaining a necessary distance which is adistance from an end of the image sensor 61 to an end of the rigidsubstrate 53. As illustrated in FIG. 17, a necessary distance is adistance corresponding to an overlap width and a width for wire bondingfrom an end of the rigid substrate 53. It should be noted that inpractice, a distance considering tolerance and mounting accuracy forpreventing an overlap between a wire-bonding pad of the rigid substrate53 and the connection terminal portion 53 a, in addition to the overlapwidth and the width for wire bonding, serves as a necessary distance.

FIGS. 18A and 18B are plan views seen from above of FIG. 17. In thefigure, illustration of the lens unit 51 is omitted for easyunderstanding.

As illustrated in FIG. 18A, one end of a wire 63 is connected with eachof electrode pads (squares in the figure) provided by being aligned in avertical direction on the right side in the figure and on the left sidein the figure of the image sensor 61. Further, the other end of the wire63 is connected with each of the electrode pads (squares in the figure)provided by being aligned in a vertical direction on the right side inthe figure and on the left side in the figure of the rigid substrate 53.

The electrode pads of the rigid substrate 53 are connected with theconnection terminal portions 53 a through the wiring formed in the rigidsubstrate 53, respectively.

Then, as illustrated in FIG. 18B, the flexible substrate 54 is attached,in an overlapped manner, to the connection terminal portions 53 a of therigid substrate 53. At this time, a distance from the end on the rightside, in the figure, of the image sensor 61 to the end on the left side,in the figure, of the flexible substrate 54 is a necessary distance.

If the rigid substrate 53 is designed so as to have such a necessarydistance, it is difficult to reduce the size of the rigid substrate 53.Consequently, further reduction in size of the camera module isdifficult.

As such, as illustrated in FIG. 19, it is acceptable that the other endof the wire 63, connected with the electrode pad of the image sensor 61,is directly connected with the flexible substrate 54, for example. Inthe case of the connection as illustrated in FIG. 19, as the width forwire bonding can be reduced significantly, the necessary distance can beshortened compared with the case of FIG. 17, for example.

In the case where the other end of the wire 63, connected with theelectrode pad of the image sensor 61, is directly connected with theflexible substrate 54, an electrode pad may be formed by forming anopening by punching a portion of an end portion of the flexiblesubstrate 54 on which wiring is not formed, and embedding metal or thelike in the opening, for example.

FIGS. 20A and 20B are diagrams explaining punching of the flexiblesubstrate 54.

FIG. 20A is a plan view illustrating an example of punching of theflexible substrate 54. In this example, an end portion on the left side,in the figure, of the flexible substrate 54 is punched to thereby formopenings 54 e aligned in a vertical direction. As illustrated in thefigure, the openings 54 e are formed at positions on the surface of theflexible substrate 54 where wiring 54 f is not formed.

It should be noted that the flexible substrate 54 has a multilayerstructure, and is formed such that four layers of substrates arelayered. Further, on the uppermost substrate of the flexible substrate54, wiring is not formed. In FIG. 20A, a plurality of lines extending ina horizontal direction in the figure schematically represent that thewiring 54 f formed in the flexible substrate 54 is seen through theuppermost substrate.

FIG. 20B is a side view corresponding to FIG. 20A. As illustrated in thefigure, the opening 54 e is formed so as to penetrate from the surfaceto the bottom face of the flexible substrate 54, and is formed at aposition where wiring 54 g, wiring 54 h, or wiring 54 i is not formedinside the flexible substrate 54. This means that all of the layers ofthe flexible substrate 54 having a multilayer structure are punched tothereby form the opening 54 e.

In the opening 54 e, metal is embedded. The metal to be embedded here isAu or a metal having high connectivity with the electrode pad of theimage sensor 61, for example. Further, if the thickness of the flexiblesubstrate 54 is about 100 μm, metal to be embedded may be one in whichthe surface of a metal such as Ni is plated by Au, for example, ratherthan a single metal.

FIGS. 21A and 21B are side views explaining a connecting method betweenthe rigid substrate 53 and the flexible substrate 54.

As illustrated in FIG. 21A, metal is embedded in the opening 54 e tothereby form an embedded electrode 71. The embedding method may be amethod such as a squeegee printing, for example. The embedded electrode71 is connected with an electrode pad 72 of the rigid substrate 53through metal bonding by heat or ultrasonic waves. This means that theembedded electrode 71 is directly welded to the electrode pad 72.

By directly welding the metals in this way, the bonding strength betweenthe rigid substrate 53 and the flexible substrate 54 is enhanced.

The electrode pad 72 is electrically connected with wiring 73 inside therigid substrate 53. The wiring 73 of the rigid substrate 53 is connectedwith the wiring 54 i of the flexible substrate 54, and the rigidsubstrate 53 and the flexible substrate 54 are attached to each otherwith an adhesive such as ACF, an adhesive containing solder (SAM, or thelike), or the like.

Here, the wiring 73 of the rigid substrate 53 corresponds to a terminalof the connection terminal portion 53 a, for example, and the wiring 54i of the flexible substrate 54 corresponding to a terminal of aconnection terminal portion of the flexible substrate 54, for example.

Then, as illustrated in FIG. 21B, the electrode pad 61 a of the imagesensor 61 and the embedded electrode 71 are connected with each other bywire bonding through the wire 63. Thereby, the electrode pad 61 a of theimage sensor 61 and the wiring 54 i of the flexible substrate 54 areconnected with each other electrically.

FIG. 22 is a plan view seen from above of FIGS. 21A and 21B.

As illustrated in FIG. 22, one end of a wire is connected with each ofthe electrode pads provided by being aligned in a vertical direction onthe right side in the figure and on the left side in the figure of theimage sensor 61. The flexible substrate 54 is attached so as to overlapthe connection terminal portions 53 a of the rigid substrate 53, and theother end of the wire 63, connected with the electrode pad 61 a on theright side in the figure, is connected with the embedded electrode 71embedded in the flexible substrate 54. In this case, a distance from theend on the right side, in the figure, of the image sensor 61 to the endon the left side, in the figure, of the flexible substrate 54 is anecessary distance.

It should be noted that in FIG. 22, the electrode pads on the left sidein the figure of the image sensor 61 are connected with the electrodepads of the rigid substrate 53 through wires.

With this configuration, as the width for wire bonding can be reducedsignificantly, the necessary distance can be shortened, compared withthe case of FIGS. 18A and 18B, for example. Thereby, it is possible tofurther reduce the size of the camera module.

In the example described above with reference to FIGS. 21A and 21B,while description has been given on the example of the case where theembedded electrode 71 is embedded in the opening 54 e of the flexiblesubstrate 54 by a method such as squeegee printing, it is possible toform a stud bump, instead of embedding the embedded electrode 71.

FIGS. 23A and 23B are side views explaining another example of aconnecting method between the rigid substrate 53 and the flexiblesubstrate 54.

As illustrated in FIG. 23A, a stud bump 81 is formed in the opening 54e. The stud bump 81 is connected with the electrode pad 72 of the rigidsubstrate 53 through metal bonding by heat or ultrasonic waves. Thismeans that the stud bump 81 is directly welded to the electrode pad 72.

By directly welding the metals in this way, the bonding strength betweenthe rigid substrate 53 and the flexible substrate 54 is enhanced.

The electrode pad 72 is electrically connected with the wiring 73 insidethe rigid substrate 53. The wiring 73 of the rigid substrate 53 isconnected with the wiring 54 i of the flexible substrate 54, and therigid substrate 53 and the flexible substrate 54 are attached to eachother with an adhesive of ACF, for example.

Then, as illustrated in FIG. 23B, the electrode pad 61 a of the imagesensor 61 and the stud bump 81 are connected by wire bonding through thewire 63. Thereby, the electrode pad 61 a of the image sensor 61 and thewiring 54 i of the flexible substrate 54 are electrically connected.

It should be noted that after the stud bump 81 is formed, the rigidsubstrate 53 and the flexible substrate 54 may be overlapped andattached to each other by aligning the position of the stud bump 81 andthe position of the opening 54 e.

Meanwhile, in the embodiment described above with reference to FIGS.21A, 21B, 22, 23A and 23B, the embedded electrode 71 or the stud bump 81formed in the opening 54 e of the flexible substrate 54 is connectedwith the electrode pad 72 of the rigid substrate 53, and is electricallyconnected with the wiring 73 inside the rigid substrate 53. In thiscase, a signal output from the image sensor 61 is transmitted from theflexible substrate 54 through the rigid substrate 53 once, and istransmitted to the flexible substrate 54 again.

However, if a signal output from the image sensor 61 is transmitted tothe flexible substrate 54 and is directly transmitted inside theflexible substrate 54, the wiring in the rigid substrate 53 can befurther simplified. Further, as a signal output from the image sensor 61is transmitted not through the connection terminal portion 53 a of therigid substrate 53, it is possible to reduce impedance associated withconnection of the terminals, and further, to reduce the number ofterminals in the connection terminal portions 53 a.

FIG. 24 is a side view explaining still another example of a connectingmethod between the rigid substrate 53 and the flexible substrate 54.

In the example of FIG. 24, a pad 85 is formed on the upper side in thefigure of the flexible substrate 54. The pad 85 is wire-bonded to theelectrode pad 61 a of the image sensor 61 through the wire 63, and asignal output from the image sensor 61 is transmitted inside theflexible substrate 54 through the wiring 54 j and the like.

FIG. 25, which is part of FIG. 24, is a diagram illustrating an enlargedconnecting portion between the flexible substrate 54 and the rigidsubstrate 53.

As illustrated in FIG. 25, a signal supplied through the wire 63connected with the pad 85 is transmitted inside the flexible substrate54 through the wiring 54 j and the like, not through the rigid substrate53. On the other hand, a signal transmitted through the wiring and thelike in the rigid substrate 53 is transmitted to the flexible substrate54, by the wiring 73 (terminal of the connection terminal portion 53 a)of the rigid substrate 53 and the wiring 54 i (terminal of theconnection terminal portion) of the flexible substrate being connectedwith each other with ACF, an adhesive containing solder, or the like.

As illustrated in FIG. 25, in the case of forming the pad 85, in theflexible substrate 54 having a multilayer structure, the pad 85 may beformed by forming an opening by punching an end portion of the uppermostlayer, and embedding metal in the opening, for example. In this step,metal is embedded in the opening by squeegee printing or the like.

FIGS. 26A and 26B are diagrams explaining punching of the flexiblesubstrate 54 when forming the pad 85 illustrated in FIG. 25.

FIG. 26A is a plan view illustrating an example of punching of theflexible substrate 54. In this example, an end portion on the left side,in the figure, of an uppermost layer 54-1 of the flexible substrate 54is punched to thereby form openings 54-1 e aligned in a verticaldirection.

FIG. 26B is a side view corresponding to FIG. 26A. As illustrated in thefigure, the opening 54-1 e is formed so as to penetrate only theuppermost layer 54-1 of the flexible substrate 54.

FIGS. 27A and 27B are diagrams illustrating a configuration of theentire flexible substrate 54 configured to include the uppermost layer54-1 illustrated in FIG. 26A and FIG. 26B.

FIG. 27A is a plan view of the entire flexible substrate 54 configuredto include the uppermost layer 54-1. In this example, the flexiblesubstrate 54 has a four-layer structure. In FIG. 27A, the uppermostlayer 54-1 adheres to the other three layers, and a plurality of linesextending in a horizontal direction in the figure schematicallyrepresent that the wiring 54 f formed in the flexible substrate 54 isseen through the uppermost substrate.

FIG. 27B is a side view corresponding to FIG. 27A. As illustrated in thefigure, the opening 54-1 e only penetrates the uppermost layer 54-1 ofthe flexible substrate 54, and no opening is formed in the lower layers.

With this configuration, as the width for wire bonding can be reducedsignificantly, the necessary distance can be shortened compared with thecase of FIGS. 18A and 18B, for example. Thereby, it is possible tofurther reduce the size of the camera module.

Further, as a signal output from the image sensor 61 is transmitted tothe flexible substrate 54 and is directly transmitted inside theflexible substrate 54, the wiring in the rigid substrate 53 can befurther simplified.

Further, as a signal output from the image sensor 61 is transmitted notthrough the connection terminal portion 53 a of the rigid substrate 53,it is possible to reduce impedance associated with connection of theterminal, and further, to reduce the number of terminals in theconnection terminal portion 53 a.

Alternatively, in the flexible substrate 54, the pad 85 as illustratedin FIG. 25 and the embedded electrode 71 as illustrated in FIGS. 21A and21B (or the stud bump 81 as illustrated in FIGS. 23A and 23B) may beformed so as to be provided together.

As described above, in the flexible substrate 54, if the pad 85 isformed, impedance associated with connection of the terminal can bereduced. On the other hand, in order to improve bonding strength betweenthe rigid substrate 53 and the flexible substrate 54, it is effective toform the embedded electrode 71 or the stud bump 81.

For example, a wire for a signal having high resistance to noise, amongthe signals transmitted from and received by the image sensor 61, isallowed to be connected with the embedded electrode 71 or the stud bump81, and the other wires for a signal are allowed to be connected to thepad 85, for example. In this way, if the pad 85 and the embeddedelectrode 71 (or stud bump 81) are provided together, it is possible toimprove the bonding strength between the rigid substrate 53 and theflexible substrate 54 without lowering the SI (Signal Integrity).

In the example described above with reference to FIGS. 24, 25, 26A, 26B,27A and 27B, description has been given on the example in which anopening is formed in the flexible substrate 54, whereby the embeddedelectrode 71, the stud bump 81, or the pad 85 is formed and wire-bondingis performed. However, it is also acceptable to perform wire bonding tothe electrode pad provided on the surface of the uppermost layer 54-1 ofthe flexible substrate 54, without forming an opening in the flexiblesubstrate 54.

Further, when performing wire bonding to the electrode pad provided onthe surface of the uppermost layer 54-1 of the flexible substrate 54, aform of on bump bonding (ball stitch on ball bonding) may be taken. Onbump bonding is a form in which a bump is formed on an electrode pad inadvance, and second bonding is performed on the bump.

Meanwhile, the embodiment described above with reference to FIGS. 19,20A, 20B 21A, 21B, 22, 23A, 23B 24, 25, 26A, 26B, 27A and 27B hasdescribed an example in which the other end of the wire 63, connectedwith the electrode pad of the image sensor 61, is directly connectedwith the flexible substrate 54, whereby the size of the camera module isreduced.

However, it is also possible to reduce the size of the camera module byadopting another method. For example, it is possible to reduce the sizeof the camera module by making the electrode pads aligned in a verticaldirection of the rigid substrate 53 and the terminals of the connectionterminal portion 53 a of the rigid substrate 53 common.

As described with reference to FIG. 18A, one end of the wire 63 isconnected with each of the electrode pads (squares in the figure)provided to be aligned in a vertical direction on the right side in thefigure and on the left side in the figure of the image sensor 61.Further, the other end of the wire 63 is connected with each of theelectrode pads (squares in the figure) provided to be aligned in avertical direction on the right side in the figure and on the left sidein the figure of the rigid substrate 53. Here, each of the electrodepads provided to be aligned on the right side, in the figure, of therigid substrate is an electrode pad 53 b.

FIG. 28 is an enlarged view of part of the electrode pads 53 b and theconnection terminal portion 53 a in FIG. 18A. FIG. 28 illustrateselectrode pads 53 b-1 to 53 b-5, and terminals 53 a-1 to 53 a-5 in theconnection terminal portion 53 a.

The electrode pad 53 b-1 is connected with the wiring inside (in thelower layer of) the rigid substrate 53 through a via V11, and isconnected with a via, not shown, through the wiring, to thereby beelectrically connected with a terminal connected with the via. Further,the terminal 53 a-1 is connected with the wiring inside (in the lowerlayer of) the rigid substrate 53 through a via V21, and is connectedwith an electrode pad or the like, not shown, through the wiring.

The electrode pad 53 b-2 is directly connected with the terminal 53 a-2through the wiring in the surface layer of the rigid substrate 53 tothereby be electrically connected with the terminal 53 a-2.

The electrode pad 53 b-3 is directly connected with the terminal 53 a-3through the wiring in the surface layer of the rigid substrate 53 tothereby be electrically connected with the terminal 53 a-3.

The electrode pad 53 b-4 is connected with the wiring inside (in thelower layer of) the rigid substrate 53 through a via V12, and isconnected with a via, not shown, through the wiring, to thereby beelectrically connected with a terminal connected with the via. Further,the terminal 53 a-4 is connected with the wiring inside (in the lowerlayer of) the rigid substrate 53 through a via V22, and is connectedwith an electrode pad or the like, not shown, through the wiring.

The electrode pad 53 b-5 is directly connected with the terminal 53 a-3through the wiring in the surface layer of the rigid substrate 53 tothereby be electrically connected with the terminal 53 a-5.

In this way, by passing through the wiring inside (in the lower layerof) the rigid substrate 53 or the wiring in the surface layer of therigid substrate 53, a distance between the electrode pad 53 b and theconnection terminal portion 53 a must be longer. Accordingly, anecessary distance, which is a distance corresponding to the overlapwidth and the width for wire bonding, from an end of the rigid substrate53, also becomes longer.

As such, as illustrated in FIG. 29, the electrode pads provided to bealigned in a vertical direction of the rigid substrate 53 and theterminals in the connection terminal portion 53 a are made common, forexample. In the example of FIG. 29, the electrode pads provided atpositions near the connection terminal portion 53 a and aligned in avertical direction on the right side, in the figure, of the rigidsubstrate 53, are made common to the terminals in the connectionterminal portion 53 a.

It should be noted that in FIG. 29, the terminals in the connectionterminal portion 53 a are classified into three, in which a terminalgroup provided on the upper side in the figure is a terminal group Tm1,a terminal group provided in the middle in the figure is a terminalgroup Tm2, and a terminal group provided on the lower side in the figureis a terminal group Tm3. Among the terminal groups Tm1 to Tm3, aterminal group which is made common to the electrode pads provided to bealigned in a vertical direction on the right side in the figure of therigid substrate 53 is the terminal group Tm2. The terminal group Tm1 andthe terminal group Tm3 are not made common to the electrode padsprovided to be aligned in a vertical direction on the right side in thefigure of the rigid substrate 53.

FIG. 30 is an enlarged view of part of the terminal group Tm2 in FIG.29. FIG. 30 illustrates the terminals 53 a-1 to 53 a-5 in the connectionterminal portion 53 a.

The terminals 53 a-1 to 53 a-5 in FIG. 30 are terminals having largerareas compared with the case of the terminals 53 a-1 to 53 a-5 in FIG.28. To each of the terminals 53 a-1 to 53 a-5, the other end of the wire63, in which one end thereof is connected with the electrode pad of theimage sensor 61, is wire bonded. Further, to each of the terminals 53a-1 to 53 a-5, a connection terminal of the flexible substrate 54 isattached.

Further, the terminal 53 a-5 is configured to be connected with thewiring inside (in the lower layer of) the rigid substrate 53 through avia V23. The terminal 53 a-5 is, for example, a terminal of a powersource or GND, and is connected with the power source or the GND throughthe wiring inside (in the lower layer of) the rigid substrate 53.

FIG. 31 is a cross-sectional view corresponding to FIG. 18B, and is across-sectional view taken along a line in a horizontal direction in thefigure passing through the center of the image sensor 61 in FIG. 18B. Asillustrated in the figure, one end of the wire 63 is connected with theelectrode pad on the image sensor 61, and the other end of the wire 63is connected with the electrode pad 53 b of the rigid substrate 53.

FIG. 32 is a cross-sectional view corresponding to FIG. 29, and is across-sectional view taken along a line in a horizontal direction in thefigure passing through the center of the image sensor 61 in FIG. 18B. Asillustrated in the figure, one end of the wire 63 is connected with theelectrode pad on the image sensor 61, and the other end of the wire 63is connected with the terminal in the connection terminal portion 53 aon the rigid substrate 53. Further, in the case of FIG. 32, theelectrode pads (electrode pad 53 b in FIG. 31) provided to be aligned onthe right side in the figure of the rigid substrate 53 are made commonto the terminals of the connection terminal portion 53 a.

By adopting the configuration illustrated in FIG. 32, it is possible toshorten the length in a horizontal direction in the figure of the rigidsubstrate 53. This means that a length L22 in a horizontal direction inthe figure of the rigid substrate 53, in the configuration illustratedin FIG. 32, is shorter than a length L21 in a horizontal direction inthe figure of the rigid substrate 53 in the configuration illustrated inFIG. 31. As such, a necessary distance which is a distance from an endof the rigid substrate 53 corresponding to the overlap width and thewidth for wire bonding, can also be shortened.

In this way, according to the present technology, the size of a cameramodule can be further reduced.

As described above, a camera module to which the present technology isapplied is to be installed in an electronic device such as a mobiletelephone, a smartphone, or the like. FIG. 33 is a block diagramillustrating an exemplary inner configuration according to an embodimentof a mobile telephone to which the present technology is applied.

In a mobile telephone 100 illustrated in FIG. 33, a communicationantenna 112 is a built-in antenna, for example, and performstransmission and reception of signal wave for telephone calls and packetcommunications such as e-mails. A communication circuit 111 performsfrequency conversion, modulation, and demodulation oftransmission/reception signals.

A speaker 120 is a speaker for receiving voices provided in the mobiletelephone 100, or a speaker for outputting ringer (incoming calls),alarm sound, and the like, and converts sound signals supplied from acontrol and arithmetic unit 110 into acoustic waves and outputs them tothe air.

A microphone 121 is a microphone for voice transmission and collectionof outside sound, and converts acoustic waves to sound signals andtransmits the sound signals to the control and arithmetic unit 110.

A display unit 113 includes a display device such as a liquid crystaldisplay or an organic EL display, and a display drive circuit of thedisplay, and displays various types of characters and images such ase-mails, for example, on the display by image signals supplied from thecontrol and arithmetic unit 110, and if captured images are suppliedfrom the camera unit 124, displays the captured images.

An operation unit 114 is configured of various keys such as numerickeys, a call key, an end/power key, and the like provided on the casingof the mobile telephone 100, various operators such as a cross key, ashutter button, and a horizontal photographing mode switch, and anoperation signal generator which generates operation signals when thoseoperators are operated. It should be noted that if the mobile telephone100 has a touch panel, the touch panel is also included in the operationunit 114.

A camera unit 124 is a function block equivalent to the camera module 50described above with reference to FIGS. 4 to 16. This means that as thecamera unit 124, the camera module 50 to which the present technology isapplied is disposed. An image signal captured by the camera unit 124 isapplied with various types of image processing by the control andarithmetic unit 110, and then, is displayed on the display screen of thedisplay unit 113, is compressed and stored in a memory unit 116, or thelike.

The memory unit 116 includes a built-in memory provided inside theterminal, and a detachable card memory which stores so-called SIM(Subscriber Identity Module) information and the like. The built-inmemory includes a ROM (Read Only Memory) and a RAM (Random AccessMemory). A ROM is configured of a rewritable ROM such as a NAND-typeflash memory or an EEPROM (Electrically Erasable Programmable Read-OnlyMemory). In the ROM, an OS (Operating System) program, a control programfor controlling the respective units by the control and arithmetic unit110, various application programs, dictionary data, sound data such asincoming call sound and key operation sound, image data captured by thecamera unit 124, and the like are stored.

A RAM stores data from time to time, as a work region when the controland arithmetic unit 110 performs various types of data processing.

The control and arithmetic unit 110 is configured of a CPU (centralprocessing unit), and performs control of communications in thecommunication circuit 111, sound processing and control thereof, imageprocessing and control thereof, control of image capturing by the cameraunit 124, control of other various types of signal processing andrespective units, and the like. Further, the control and arithmetic unit110 performs execution of various types of control programs andapplication programs stored in the memory unit 116, and various types ofdata processing associated therewith, and the like.

In addition, although not shown, components provided to a typical mobiletelephone 100 are also provided, which includes a current positiondetection unit using GPS (Global Positioning System) satellite waves, acontactless communication unit which performs contactless communicationsused in a contactless IC card, and the like, a power management IC unitwhich controls a battery for supplying power to respective units and thepower thereof, a slot for external memory, a receiving tuner for digitalbroadcasting, an AV codec unit, and the like.

While an example in which a camera module, to which the presenttechnology is applied, is installed in a mobile telephone has beendescribed herein, a camera module, to which the present technology isapplied, can be installed in various types of electronic devices such asa smartphone and a tablet device.

Further, the embodiment of the present technology is not limited to theabove-described embodiment, and various changes can be made within thescope of the gist of the present technology.

It should be noted that the present technology may also be configured asdescribed below.

(1)

A camera module including:

a lens unit that stores a lens that condenses light on a light receivingsurface of an image sensor;

a rigid substrate on which the image sensor is disposed; and

a flexible substrate electrically connected with the rigid substrate,wherein

in a case where the light receiving surface of the image sensor locatesat the top, the lens unit, the flexible substrate, and the rigidsubstrate are disposed in this order from the top.

(2)

The camera module according to (1), wherein

in the rigid substrate of a square shape,

in an overlap region of a band shape having a predetermined distancefrom an end of one side of the square, the rigid substrate is disposedto overlap a portion of the flexible substrate, and the rigid substrateand the flexible substrate are attached to each other.

(3)

The camera module according to (2), wherein the overlap region is aband-shaped region having a width of 2.4 mm or less.

(4)

The camera module according to (2), wherein

in the flexible substrate,

besides the overlap region, a reinforced region in which the flexiblesubstrate overlaps the rigid substrate is provided.

(5)

The camera module according to (4), wherein

the reinforced region is provided to extend in parallel with two sidesof the image sensor of the square shape.

(6)

The camera module according to (4), wherein

the reinforced region is provided to extend in parallel with one side ofthe image sensor of the square shape.

(7)

The camera module according to any of (1) to (6), wherein

in the rigid substrate of a square shape,

a solder resist is removed in a band-shaped region having apredetermined distance from an end of one side of the square.

(8)

The camera module according to any of (1) to (7), wherein

a groove for accommodating an end portion of the flexible substrate isformed in the lens unit.

(9)

The camera module according to any of (1) to (7), wherein

a frame is further provided between the lens unit and the flexiblesubstrate.

(10)

The camera module according to (9), wherein

a groove for accommodating an end portion of the flexible substrate isformed in the frame.

(11)

The camera module according to any of (1) to (10), wherein

an electrode pad of the image sensor and an embedded electrode providedin the flexible substrate are connected with each other by wire bonding,and

a signal output from the electrode pad of the image sensor istransmitted to the rigid substrate through the embedded electrode.

(12)

The camera module according to (11), wherein

the embedded electrode is formed by punching all layers of the flexiblesubstrate having a multilayer structure to thereby form an opening, andembedding metal in the opening.

(13)

The camera module according to any of (1) to (10), wherein

the electrode pad is formed by punching an uppermost layer of theflexible substrate having a multilayer structure to thereby form anopening, and embedding metal in the opening, and

an electrode pad of the image sensor and the electrode pad provided inthe flexible substrate are connected with each other by wire bonding.

(14)

The camera module according to any of (1) to (10), wherein

an electrode pad of the image sensor and a stud bump protruding on therigid substrate are connected by wire bonding.

(15)

The camera module according to (14), wherein

an opening is formed by punching all layers of the flexible substratehaving a multilayer structure, and

the stud bump is formed on an electrode pad which is on the rigidsubstrate and is located at a position corresponding to the opening.

(16)

The camera module according to any of (1) to (10), wherein

in the flexible substrate having a multilayer structure, an openingformed by punching all layers and an opening formed by punching anuppermost layer of the flexible substrate are provided in a regionconnected with an electrode pad of the image sensor by wire bonding.

(17)

The camera module according to (1), wherein an electrode pad of theimage sensor and an electrode pad of the rigid substrate are connectedwith each other by wire bonding, and

the electrode pad of the rigid substrate is made common to a connectionterminal provided on the rigid substrate for electrically connecting theflexible substrate.

(18)

The camera module according to (17), wherein

among the electrode pads and the connection terminals of the rigidsubstrate provided on a plurality of sides of the rigid substrateconfigured in a rectangle shape, only an electrode pad and a connectionterminal provided on one side of the rigid substrate are made common.

(19)

The camera module according to (18), wherein

among the connection terminals of the rigid substrate provided on theone side, only a connection terminal in a center portion of the side ismade common to the electrode pad.

(20)

The camera module according to (17), wherein

the connection terminal, made common to the electrode pad, is connectedwith wiring inside the rigid substrate through a via.

(21)

A camera module manufactured by a method including the steps of:

disposing a rigid substrate;

connecting a flexible substrate with the rigid substrate; and

disposing a lens unit on the rigid substrate, the lens unit storing alens that condenses light on a light receiving surface of the imagesensor, wherein

in the step of connecting the flexible substrate with the rigidsubstrate, in the rigid substrate of a square shape, in an overlapregion of a band shape having a predetermined distance from an end ofone side of the square, the rigid substrate is disposed to overlap aportion of the flexible substrate, and the rigid substrate and theflexible substrate are attached to each other.

(22)

An electronic device including

a camera module including:

-   -   a lens unit that stores a lens that condenses light on a light        receiving surface of an image sensor;    -   a rigid substrate on which the image sensor is disposed; and    -   a flexible substrate electrically connected with the rigid        substrate, wherein

in a case where the light receiving surface of the image sensor locatesat the top, the lens unit, the flexible substrate, and the rigidsubstrate are disposed in this order from the top.

REFERENCE SIGNS LIST

-   50 Camera module-   51 Lens unit-   52 Frame-   53 Rigid substrate-   54 Flexible substrate-   54 e Opening-   61 Image sensor-   61 a Electrode pad-   63 Wire-   71 Embedded electrode-   72 Electrode pad-   81 Stud bump-   85 Pad-   100 Mobile telephone-   124 Camera unit

The invention claimed is:
 1. A camera module, comprising: a lens unit that includes a lens, wherein the lens is configured to condense light on a light receiving surface of an image sensor; a rigid substrate, wherein the image sensor is on the rigid substrate; a flexible substrate electrically connected to the rigid substrate; a first electrode pad of the image sensor; and an embedded electrode embedded in the flexible substrate, wherein the embedded electrode is connected to the first electrode pad, wherein the light receiving surface of the image sensor faces the lens unit, wherein the lens unit, the flexible substrate, and the rigid substrate are arranged in this order from a side of the lens unit; and wherein, in the rigid substrate of a square shape, a solder resist is absent in a band-shaped region that has a specified distance from an end of one side of the rigid substrate.
 2. The camera module according to claim 1, wherein the rigid substrate overlaps a portion of the flexible substrate in an overlap of a band shape that has the specified distance from the end of the one side of the rigid substrate, and the rigid substrate is attached to the flexible substrate.
 3. The camera module according to claim 2, wherein a region of the overlap corresponds to the band-shaped region that has a width of one of 2.4 mm or less.
 4. The camera module according to claim 2, wherein the flexible substrate includes a region of the overlap, and a reinforced region in which the flexible substrate overlaps the rigid substrate.
 5. The camera module according to claim 4, wherein the reinforced region extends in a parallel direction along two sides of the image sensor, and wherein the image sensor has a square shape.
 6. The camera module according to claim 4, wherein the reinforced region extends in a parallel direction along one side of the image sensor, and wherein the image sensor has a square shape.
 7. The camera module according to claim 1, wherein the lens unit further includes a groove, and the groove accommodates an end portion of the flexible substrate.
 8. The camera module according to claim 1, further comprising a frame between the lens unit and the flexible substrate.
 9. The camera module according to claim 8, wherein the frame includes a groove, and the groove accommodates an end portion of the flexible substrate.
 10. The camera module according to claim 1, wherein the flexible substrate comprises a multilayer structure, and the embedded electrode comprises a metal embedded in an opening in each of a plurality of layers of the multilayer structure of the flexible substrate.
 11. The camera module according to claim 1, wherein the flexible substrate includes a second electrode pad, the flexible substrate comprises a multilayer structure, the second electrode pad comprises a metal embedded in an opening in an uppermost layer of a plurality of layers of the multilayer structure of the flexible substrate, and the first electrode pad of the image sensor is connected to the second electrode pad of the flexible substrate by a wire bonding process.
 12. The camera module according to claim 1, wherein the first electrode pad of the image sensor and a stud bump that protrudes on the rigid substrate are connected by a wire bonding process.
 13. The camera module according to claim 12, wherein the flexible substrate, that comprises a multilayer structure, includes an opening in each of a plurality of layers of the multilayer structure of the flexible substrate, and the stud bump is on a third electrode pad of the rigid substrate, at a position that corresponds to the opening.
 14. The camera module according to claim 1, wherein the flexible substrate, that comprises a multilayer structure, includes a first opening in each of a plurality of layers of the multilayer structure of the flexible substrate and a second opening in an uppermost layer of the plurality of layers of the multilayer structure of the flexible substrate in a region connected with the first electrode pad of the image sensor by a wire bonding process.
 15. The camera module according to claim 1, wherein the first electrode pad of the image sensor is connected to a third electrode pad of a plurality of third electrode pads of the rigid substrate by a wire bonding process, and the third electrode pad of the rigid substrate is common to a first connection terminal of a plurality of connection terminals on the rigid substrate to electrically connect the flexible substrate.
 16. The camera module according to claim 15, wherein, among the plurality of third electrode pads and the plurality of connection terminals of the rigid substrate on a plurality of sides of the rigid substrate, one of the plurality of third electrode pads or a second connection terminal of a plurality of connection terminals on the one side of the rigid substrate are common.
 17. The camera module according to claim 16, wherein, among the plurality of connection terminals of the rigid substrate present on the one side, a third connection terminal of a plurality of connection terminals in a center portion of the one side is common to a corresponding third electrode pad of the plurality of third electrode pads.
 18. The camera module according to claim 15, wherein the first connection terminal, which is common to the third electrode pad, is connected to wiring inside the rigid substrate through a via.
 19. A method for manufacturing a camera module, the method comprising: connecting a flexible substrate with a rigid substrate; and placing a lens unit on the rigid substrate, wherein the lens unit includes a lens configured to condense light on a light receiving surface of an image sensor, wherein in an overlap region of a band shape having a specified distance from an end of one side of the rigid substrate, the rigid substrate overlaps a portion of the flexible substrate and the rigid substrate is attached to the flexible substrate, wherein, in the rigid substrate of a square shape, a solder resist is absent in the overlap region of the band shape, and wherein an electrode pad of the image sensor is connected to an embedded electrode embedded in the flexible substrate.
 20. An electronic device, comprising: a camera module including: a lens unit that includes a lens, wherein the lens is configured to condense light on a light receiving surface of an image sensor; a rigid substrate, wherein the image sensor is on the rigid substrate; a flexible substrate electrically connected to the rigid substrate; an electrode pad of the image sensor; and an embedded electrode embedded in the flexible substrate, wherein the embedded electrode is connected to the electrode pad, wherein the light receiving surface of the image sensor faces the lens unit, wherein the lens unit, the flexible substrate, and the rigid substrate are arranged in this order from a side of the lens unit; and wherein, in the rigid substrate of a square shape, a solder resist is absent in a band-shaped region that has a specified distance from an end of one side of the rigid substrate. 